Sometimes a case officer’s best friend is a shiny, reflective surface to see what (or who) is behind them. In this case, the rear view is provided by a sign at the famous Theatre du Vaudeville in Paris. The last thing he’ll do is stop and look back. After all, why give pursuers a reason to think you’re up to no good? If a handler suspects someone is there, he’ll change the pace he’s walking. Every street has a certain pace to it, so he’ll start walking either slower or faster. That forces his tail to alter their pace accordingly, and stand out even more.